@@ -131,6 +131,20 @@ func hwcapCToGo(chwcap C.libxl_hwcap) (ghwcap Hwcap) {
return
}
+// typedef struct {
+// uint32_t size; /* number of bytes in map */
+// uint8_t *map;
+// } libxl_bitmap;
+
+// Implement the Go bitmap type such that the underlying data can
+// easily be copied in and out. NB that we still have to do copies
+// both directions, because cgo runtime restrictions forbid passing to
+// a C function a pointer to a Go-allocated structure which contains a
+// pointer.
+type Bitmap struct {
+ bitmap []C.uint8_t
+}
+
/*
* Types: IDL
*
@@ -198,6 +212,159 @@ type Dominfo struct {
}
/*
+ * Bitmap operations
+ */
+
+// Return a Go bitmap which is a copy of the referred C bitmap.
+func bitmapCToGo(cbm C.libxl_bitmap) (gbm Bitmap) {
+ // Alloc a Go slice for the bytes
+ size := int(cbm.size)
+ gbm.bitmap = make([]C.uint8_t, size)
+
+ // Make a slice pointing to the C array
+ mapslice := (*[1 << 30]C.uint8_t)(unsafe.Pointer(cbm._map))[:size:size]
+
+ // And copy the C array into the Go array
+ copy(gbm.bitmap, mapslice)
+
+ return
+}
+
+// Must be C.libxl_bitmap_dispose'd of afterwards
+func bitmapGotoC(gbm Bitmap) (cbm C.libxl_bitmap) {
+ C.libxl_bitmap_init(&cbm)
+
+ size := len(gbm.bitmap)
+ cbm._map = (*C.uint8_t)(C.malloc(C.size_t(size)))
+ cbm.size = C.uint32_t(size)
+ if cbm._map == nil {
+ panic("C.calloc failed!")
+ }
+
+ // Make a slice pointing to the C array
+ mapslice := (*[1 << 30]C.uint8_t)(unsafe.Pointer(cbm._map))[:size:size]
+
+ // And copy the Go array into the C array
+ copy(mapslice, gbm.bitmap)
+
+ return
+}
+
+func (bm *Bitmap) Test(bit int) bool {
+ ubit := uint(bit)
+ if bit > bm.Max() || bm.bitmap == nil {
+ return false
+ }
+
+ return (bm.bitmap[bit/8] & (1 << (ubit & 7))) != 0
+}
+
+func (bm *Bitmap) Set(bit int) {
+ ibit := bit / 8
+ if ibit+1 > len(bm.bitmap) {
+ bm.bitmap = append(bm.bitmap, make([]C.uint8_t, ibit+1-len(bm.bitmap))...)
+ }
+
+ bm.bitmap[ibit] |= 1 << (uint(bit) & 7)
+}
+
+func (bm *Bitmap) SetRange(start int, end int) {
+ for i := start; i <= end; i++ {
+ bm.Set(i)
+ }
+}
+
+func (bm *Bitmap) Clear(bit int) {
+ ubit := uint(bit)
+ if bit > bm.Max() || bm.bitmap == nil {
+ return
+ }
+
+ bm.bitmap[bit/8] &= ^(1 << (ubit & 7))
+}
+
+func (bm *Bitmap) ClearRange(start int, end int) {
+ for i := start; i <= end; i++ {
+ bm.Clear(i)
+ }
+}
+
+func (bm *Bitmap) Max() int {
+ return len(bm.bitmap)*8 - 1
+}
+
+func (bm *Bitmap) IsEmpty() bool {
+ for i := 0; i < len(bm.bitmap); i++ {
+ if bm.bitmap[i] != 0 {
+ return false
+ }
+ }
+ return true
+}
+
+func (a Bitmap) And(b Bitmap) (c Bitmap) {
+ var max, min int
+ if len(a.bitmap) > len(b.bitmap) {
+ max = len(a.bitmap)
+ min = len(b.bitmap)
+ } else {
+ max = len(b.bitmap)
+ min = len(a.bitmap)
+ }
+ c.bitmap = make([]C.uint8_t, max)
+
+ for i := 0; i < min; i++ {
+ c.bitmap[i] = a.bitmap[i] & b.bitmap[i]
+ }
+ return
+}
+
+func (bm Bitmap) String() (s string) {
+ lastOnline := false
+ crange := false
+ printed := false
+ var i int
+ /// --x-xxxxx-x -> 2,4-8,10
+ /// --x-xxxxxxx -> 2,4-10
+ for i = 0; i <= bm.Max(); i++ {
+ if bm.Test(i) {
+ if !lastOnline {
+ // Switching offline -> online, print this cpu
+ if printed {
+ s += ","
+ }
+ s += fmt.Sprintf("%d", i)
+ printed = true
+ } else if !crange {
+ // last was online, but we're not in a range; print -
+ crange = true
+ s += "-"
+ } else {
+ // last was online, we're in a range, nothing else to do
+ }
+ lastOnline = true
+ } else {
+ if lastOnline {
+ // Switching online->offline; do we need to end a range?
+ if crange {
+ s += fmt.Sprintf("%d", i-1)
+ }
+ }
+ lastOnline = false
+ crange = false
+ }
+ }
+ if lastOnline {
+ // Switching online->offline; do we need to end a range?
+ if crange {
+ s += fmt.Sprintf("%d", i-1)
+ }
+ }
+
+ return
+}
+
+/*
* Context
*/
var Ctx Context